鸡lmbr1基因内含子多态与趾型的关联

 【目的】多趾是丝羽乌骨鸡的品种特征之一，但其多趾发生的分子机制尚未知。Lmbr1基因是人和鼠轴前多趾的关键候选基因，其同源基因是否是鸡多趾表型的关键候选基因值得研究。【方法】本研究以多趾的丝羽乌骨鸡和四趾的白洛克肉鸡杂交建立的资源家系为研究素材，采用直接测序和PCR-SSCP相结合的方法进行了鸡lmbr1基因内含子13的克隆、多态分析及其在不同物种的序列保守性比较、单体型分析及单核苷酸多态与趾型的关联分析。【结果】从内含子13检测到4个SNPs，发现这些单核苷酸多态构成的单体型在丝羽乌骨鸡和白洛克肉鸡间的分布呈现明显的差异，PCR-SSCP基因型在资源家系亲代和F2代均呈现与趾型的显著关联。【结论】 鸡lmbr1基因内含子13变异与调控鸡多趾表型的特异性位点紧密连锁，鸡lmbr1基因应是鸡多趾表型的重要候选基因，今后应进一步加大鸡lmbr1基因全基因组水平和其临近区域基因的检测。

The Association of Single Nucleotide Polymorphisms in Chicken Lmbr1 Intron with Chicken Polydactyl

【OBJECTIVE】Lmbr1 is the key candidate gene underlying human and mouse preaxial polydactyly(PPD), the mapping result of chicken polydactyl and comparative genomic analysis of polydacytlous traits among other species shows that lmbr1 should be the potential critical candidate gene of chicken PPD;【METHOD】Here we conduct the cloning of chicken lmbr1 intron 13, the Single Nucleotide Polymorphisms(SNPs) analysis, the sequence conservation among several species ,the halpotype distribution and the association of gene polymorphisms with toe phenotype with direct sequencing and PCR-SSCP methods in resource population established by polydactlous silkies and four-toed White Plymouth Rock broiler ;【RESULTS】4 SNPs were detected from Silkies and White Plymouth Rock from these region；and it was found that PCR-SSCP genotypes of intron 13 were significantly associated with chicken toe phenotype;【CONCLUSION】 it shows that the variations of lmbr1 intron 13 were tightly linked with the special site underlying chicken polydactlous mutant ,which means that lmbr1 should be the key candidate gene of chicken polydactyl, so the next step work should be to further detect the gene polymorphisms in whole genomic level of lmbr1 and its surrounding genes .